Boring mechanism.



W. H. COWELL.

BORING MECHANISIVI.

`APPLICATION FILED Nov.22, 1915.

1,2299. Patented Mar. 27, 1917.

'sa D sTAS vPME' @ENCE i WILLIAM H. COWELL, F COLUMBUS, OHIO.

BORING MECHANISM.

Specication of Letters Patent.

Patented Mari 2'?, 191'?.

Application led November 22, 1915. Serial No. 62,717.

` 1o vention is to provide meansof simpliiedV and economical construction especially adapted for reboring tubular objects, such as engine cylinders. .A further object is to so construct such means that it can be quickly and accurately applied to the cylinder for the purpose of boring.

The invention is embodied in the construction shown and described and then particularly claimed.

In the accompanyingr drawings- Figure 1 is a view illustrating the invention partly in elevation and partly in section. v

Fig. 2 is a plan and sectional view of the line :1c- Fig. 1 looking down. v

Fig. 3 is a similar view on the line g/-y Fig. 1. A

1n Fig. 1 the characters 5, 5 designate a pair of engine cylinders., 'In one of the cylinders-the right hand one-is secured an expansion mandrel of ordinary construction, said mandrel including central expanding female members 6, opposing and coperating male members .7, 7, a post 8 and av screw 9 to draw the male members toward.

each other to. spread the female members and thereby secure .the post 8 in desired xed position. rThe post has a table 8'1 to receive one side of a ring 10 constituting one member of a centering device for the tubular shaft 14 of the boring tool which is'to bore the adjacent cylinder as hereinafter explained. rlhe said ring is secured to the table by means of a bolt 11 passed through 4:5 a slot inthe ring. The other side of the 13 is of such diameter'as to have considerable horizontal play thereon in all directions on the shoulder 10a, but the ring 10 is provided with several set screws 10c ad justable against the tapering rim 13'rl to fix the ring 13in any position to which it may be moved on the shoulder 10a.

The vtubular shaft of the boring tool,

which shaft is designated 14, has upon it a downwardly tapering thimble 15 engaged by the bearing surface 13" of the inner ring 1,3. The lower end of this tubular shaft contains a suitable head 16 for carrying suitable boringtools 17 which need not ybe further described as these do not constitute the subject of the present application for patent. Upon the upper portion of the tu- `bular shaft 14 abovethe centering device is secured a vgear wheel 18 through which the said shaft is-rotated. Loose upon said tubulartool shaft above the gear 18 is a sleeve 19 fixed on the shaft tomove vertically therewith by means of a cdllar 20, having set screw 20EL to secure the collar to the tubular shaft. Vlfithin the tubular shaft is a bar 21 having at its lower end a centering device comprising a head 22 and movable radial pins 23 of equal length; The lower end of the bar 21 is made conical, as seen at 24', and is threaded, as at 25, toV receive said head so that by turning said head on the bar or reversely turning the bar in the head the projection of the pms 23 canzhe A made greater or less to impinge against the wall ofA the cylinder to be bored. This device serves to center the tubular tool bearing shaft at its lower end while the ring 13 is 'manipulated to properly aline the upper portion of said shaft.

rlhe tool shaft is driven by means of a gear wheel 26 on a shaft 27 parallel to the tubular tool shaft, said shaft being supported in a suitable bracket 28 bolted to the 10. The shaft 27 is provided with a longitudinal groove 27EL engaged by a spline 26a. The gear wheel 26 is flanged to travel with the gear Wheel 18. On the lower portion of the shaft 27 opposite the collar 19. is a loose collar 29 and connecting these two collars is a bridge 30, and on the upper'portion of said shaft 27 is a collar 31 connected by a bridge 32 with a collar 333l clamped to the upper end of the bar 21. Y

' Threadedly engaging the bridge 32 is a feed screw 34: having its lower end swiveled to the bridge 30 and provided with a star Wheel 35 having its teeth arranged to be outer ring struck by one or more pins 36 on the upper iside of the gear wheel 18 when the same is driven.l The feed screw 34 thus raises or lowers the tubular tool carrying shaft according to the direction in which the said gear is turned. The shaft 27 is shown to be provided at its lower end with a bevel gear 37 engaged by another bevel gear 38 on a power shaft 39 supported in a bracket 28 which shaft can be turned by hand or other power as may be desired.

In practice the centering device at the lower end of the bar 21 is first placed in position withinfthe cylinder to be bored but when this is being done the boring tool is not yet withinthe cylinder. The boring device 1s then seated and properly adjusted with its several cutting tools resting on the usual beveled edge 5 of the cylinder after which the set'fscrews l()c are turned up to 'fix the inner` ring 13 with reference to the outer ring 10. It will be this connection that t e rounded inner rim 13b permits of the rocking of the ring on the thimble to obtain an accurate centermg and alining of the tool shaft for subsequent boring.

The'cylinder is bored from the open end l downward, and when the cutter head nearly or quite reaches the centering device the clamp 33 is released and the centering pins 23 released by applying a wrench to the squared upper end of the guide bar or shaft 21. This permits the guide bar 21 to drop below the wearing surface of the cylinder and makes room for the cutter head to complete the boring for the full length of piston travel. What I claim is:

1. A boring mechanism including in combination, a tubular tool carrying shaft, 'a

articularly noted in bar in said tubular tool carrying shaft, a centering device on said bar for centering one end of the tool carrying shaft, said centering device constructed to engage the inner surface of the wall of the object to be bored,

and a supplementary centering device vfor the other end of the tool shaft. 2. In a boring mechanism, a centering device for a tool carrying shaft including, in

combination a Xed ring, a second ring engaging the tool shaft adjustable on the first mentioned ring, said last named ring having a rounded inner bearing surface, and

means for fixing said second ring with reference to the first mentioned ring. 3. In a boring mechanism, a centering device for a tool carrying shaft including, in

combination a fixed ring, a second ring, said last named vring having a rounded inner.,

bearing surface, a thimble on the shaft engagedA by said rounded surface and means for fixing said second ring with reference to the first mentioned ring.

4. In boring mechanism, in combination, a

said tool carrying shaft on said guide bar and feeding the same.

WILLIAM rLcownLL.V 

